class_docstr: A wrapper class for openai client.
docstr: Calculate the cost of the response.
docstr_tok: ["Calculate","the","cost","of","the","response","."]
code: def cost(self, response: Union[ChatCompletion, Completion]) -> float:
      """Calculate the cost of the response."""
      model = response.model
      if model not in OAI_PRICE1K:
          # TODO: add logging to warn that the model is not found
          logger.debug(
              f"Model {model} is not found. The cost will be 0.",
              exc_info=True,
          )
          return 0
  
      n_input_tokens = response.usage.prompt_tokens  # type: ignore [union-attr]
      n_output_tokens = response.usage.completion_tokens  # type: ignore [union-attr]
      tmp_price1K = OAI_PRICE1K[model]
      # First value is input token rate, second value is output token rate
      if isinstance(tmp_price1K, tuple):
          return (tmp_price1K[0] * n_input_tokens + tmp_price1K[1] * n_output_tokens) / 1000  # type: ignore [no-any-return]
      return tmp_price1K * (n_input_tokens + n_output_tokens) / 1000
  
imports: from __future__ import annotations
  import os
  import sys
  from typing import Any, List, Optional, Dict, Callable, Tuple, Union
  import logging
  import inspect
  from flaml.automl.logger import logger_formatter
  from pydantic import BaseModel
  from autogen.oai import completion
  from autogen.oai.openai_utils import DEFAULT_AZURE_API_VERSION, get_key, OAI_PRICE1K
  from autogen.token_count_utils import count_token
  from autogen._pydantic import model_dump
label_desc: Use image node_id 15 for calling the OpenAIWrapper obj's underlying member method code with example usage: obj.cost(response) and returns: unknown, int, unknown